I've got a url having a parameter inside it. For example:

domain.com/guidelines/index.php?doc=html 

I wish to convert this to:

domain.com/guidelines/html

Yes, it can be done with .htaccess however i can't appear to have it to operate.

Ideas?

To gain access to the param in php with $_GET['doc'], and also have the user begin to see the clean url /guidelines/html you are able to rewrite the following:

RewriteBase /
RewriteRule ^/guidelines/(.*)$ /guidelines/index.php?doc=$1 [NC]